SPC Mesoscale Discussion: Severe Potential… Watch Unlikely

SUMMARY…A line of showers and thunderstorms continues to move east across Alabama into southeastern Mississippi and will pose a threat for marginal severe wind gusts and a brief tornado, but a Watch is not expected at this time.

DISCUSSION…An extensive line of showers and a few thunderstorms continues to push eastward through the area this morning. Marginal positive buoyancy and shear vectors oriented at a small angle to the line have kept the convection somewhat disorganized and below severe limits the last few hours. Some diurnal heating is ongoing through broken low-level stratus and a thin cirrus shield, bringing surface temperatures into the upper 60s in the northern part of the area and into the low 70s over the central and southern portions of the area. Although mid-level lapse rates will remain poor, this heating should allow for surface-based CAPE of 500-1250 J/kg as mid-60s dewpoints are advected northward through the area. The increase in low-level buoyancy has allowed for some minor uptick in convective intensity within the line, particularly from Birmingham to Camden, where a weak mesoscale circulation could also contribute to further convective strengthening in the next few hours. A few damaging winds and isolated severe gusts are possible with the more organized segments of the line. Although the tornado threat remains low everywhere, the threat for a brief tornado is higher over the northern portion of the area where the 0-1-km shear continues to be 25-35 kt. Overall, the threat for severe weather is low enough to preclude a Watch at this time, but trends will be monitored for additional convective strengthening in the next few hours.

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